Memantine Hydrochloride

MEMANTINE HYDROCHLORIDE- memantine hydrochloride tablet, film coated
Contract Pharmacy Services-PA

1 INDICATIONS AND USAGE

Memantine hydrochloride tablets are indicated for the treatment of moderate to severe dementia of the Alzheimer’s type.

2 DOSAGE AND ADMINISTRATION

The recommended starting dose of memantine hydrochloride tablets are 5 mg once daily. The dose should be increased in 5 mg increments to 10 mg/day (5 mg twice daily), 15 mg/day (5 mg and 10 mg as separate doses), and 20 mg/day (10 mg twice daily). The minimum recommended interval between dose increases is one week. The dosage shown to be effective in controlled clinical trials is 20 mg/day.
Memantine hydrochloride tablets can be taken with or without food. If a patient misses a single dose of memantine hydrochloride tablets, that patient should not double up on the next dose. The next dose should be taken as scheduled. If a patient fails to take memantine hydrochloride tablets for several days, dosing may need to be resumed at lower doses and retitrated as described above.
Special Populations
Renal Impairment
A target dose of 5 mg twice daily is recommended in patients with severe renal impairment (creatinine clearance of 5 to 29 mL/min based on the Cockroft-Gault equation).
Hepatic Impairment
Memantine hydrochloride tablets should be administered with caution to patients with severe hepatic impairment [see Clinical Pharmacology ( 12.3)].

3 DOSAGE FORMS AND STRENGTHS

Memantine hydrochloride tablets 5 mg: capsule-shaped, film-coated tablets are orange colored, debossed with “321” on one side and plain on the other side.
Memantine hydrochloride tablets 10 mg: capsule-shaped, film-coated tablets are gray colored, debossed with “322” on one side and plain on the other side.

4 CONTRAINDICATIONS

Memantine hydrochloride tablets are contraindicated in patients with known hypersensitivity to memantine hydrochloride or to any excipients used in the formulation.

5 WARNINGS AND PRECAUTIONS

5.1 Genitourinary Conditions

Conditions that raise urine pH may decrease the urinary elimination of memantine resulting in increased plasma levels of memantine [see Drug Interactions ( 7.1)].

6 ADVERSE REACTIONS

6.1 Clinical Trials Experience

Memantine hydrochloride was evaluated in eight double-blind placebo-controlled trials involving a total of 1,862 dementia (Alzheimer’s disease, vascular dementia) patients (940 patients treated with memantine hydrochloride and 922 patients treated with placebo) for a treatment period up to 28 weeks.
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.
Adverse Events Leading to Discontinuation
In placebo-controlled trials in which dementia patients received doses of memantine hydrochloride up to 20 mg/day, the likelihood of discontinuation because of an adverse reaction was the same in the memantine hydrochloride group (10.1%) as in the placebo group (11.5%). No individual adverse reaction was associated with the discontinuation of treatment in 1% or more of memantine hydrochloride-treated patients and at a rate greater than placebo.
Most Common Adverse Reactions In double-blind placebo-controlled trials involving dementia patients, the most common adverse reactions (incidence ≥ 5% and higher than placebo) in patients treated with memantine hydrochloride were dizziness, headache, confusion and constipation. Table 1 lists all adverse reactions that occurred in at least 2% of patients treated with memantine hydrochloride and at an incidence greater than placebo.

Table 1: Adverse Reactions Reported in Controlled Clinical Trials in at Least 2% of Patients Receiving Memantine Hydrochloride and at a Higher Frequency than Placebo-treated Patients

Adverse Reaction	Placebo (N = 922) %	Memantine Hydrochloride (N = 940) %
Body as a Whole
Fatigue	1	2
Pain	1	3
Cardiovascular System
Hypertension	2	4
Central and Peripheral Nervous System
Dizziness	5	7
Headache	3	6
Gastrointestinal System
Constipation	3	5
Vomiting	2	3
Musculoskeletal System
Back pain	2	3
Psychiatric Disorders
Confusion	5	6
Somnolence	2	3
Hallucination	2	3
Respiratory System
Coughing	3	4
Dyspnea	1	2

The overall profile of adverse reactions and the incidence rates for individual adverse reactions in the subpopulation of patients with moderate to severe Alzheimer’s disease were not different from the profile and incidence rates described above for the overall dementia population.
Seizures
Memantine hydrochloride has not been systematically evaluated in patients with a seizure disorder. In clinical trials of memantine hydrochloride, seizures occurred in 0.2% of patients treated with memantine hydrochloride and 0.5% of patients treated with placebo.